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Bookshelf: Into a Raging Sea

Into a Raging Sea: Great South African Rescues – Tony Weaver & Andrew Ingram

I insensitively packed this book for Tony to read while we were aboard MSC Sinfonia for the BirdLife cruise we took in April. It’s a rip-roaring read about various rescues that the NSRI has been involved with over the years, but – perhaps unsurprisingly – Tony wasn’t keen to read about maritime disasters (even ones that ended well) while we were at sea.

The book was produced to commemorate the 50th anniversary of the NSRI. There is an element of history – describing the origins of the organisation, and some “sea rescues of yesteryear”. But the bulk of the book describes rescues that took place in the last 15 years. Some of them, such as the sinking of the whale watching boat Miroshga off Hout Bay’s Duiker Island, will be all too familiar from the ensuing press coverage. Others were less familiar, but no less interesting to read about.

One of the things I loved about this book was that it reveals the men and women behind the daring, often dangerous rescues. The rescuers are allowed to recount the events they experienced, using their own words, and this is revealing. These rescuers are not usually lionised by the general public or, as a rule, afforded prolonged media attention, and neither does this book glamorise them or romanticise their achievements. The challenge of the rescues – and occasional raw fear felt by the rescuers – are vividly portrayed. The writing is beautifully matter of fact, without downplaying the seamanship, strength of character and perseverance required to do this (unpaid) work.

It reminded me fondly of the “drama in real life” stories that I used to devour from the pages of the Readers Digest magazines my grandmother used to bring whenever she came to visit. There are many, short chapters, each one offering its own little catharsis. The rescues span South Africa’s coastline, as well as a few other locations, and not all of them are maritime disasters.

Proceeds of this book support the NSRI. Get a copy for yourself, and all your friends. It will entertain anyone who loves a good story of heroism and adventure, and it will encourage anyone who’s feeling jaded about humanity’s capacity for good. It’s an excellent read.

You can find a copy on Loot if you’re in South Africa, otherwise here or here.

Bookshelf: Guide to Seabirds of Southern Africa

Guide to Seabirds of Southern Africa – Peter Ryan

An indispensable companion on Flock at Sea AGAIN! was this book by Peter Ryan, director of the FitzPatrick Institute of African Ornithology at the University of Cape Town. It’s a slim volume that made seabird identification much easier for us (novices) by virtue of its focus. We were at no point able to venture speculatively into the nocturnal birds of prey or the exotic parrot section of the book, as often happens when you put a bird book covering all of southern Africa’s birds into my paws.

The introductory sections of the book explain the ocean environment and the life history of seabirds, with sidebars on specific physiological phenomena that differentiate seabirds from other birds. These sections also provide information on conservation challenges facing seabirds, and some tips on how to watch them. The geographic range covered by the book includes the sub-Antarctic islands (Marion, Tristan da Cunha, Prince Edward, Gough, Crozet, Bouvet, South Sandwich, South Georgia).

Several photographs of each bird are provided, alongside a distribution map, the bird’s measurements, and an identification guide that covers the bird’s appearance as well as call and characteristic flying style. Conservation status and an Afrikaans common name are also mentioned.

Identifying seabirds is difficult, even if you get a good record photo or have enough time to study the bird carefully. There are often subtle variants that differentiate (or don’t!) between different types of very similar-looking birds. For example, there was furious debate during and after the cruise as to whether a Tristan albatross had been seen and photographed, or whether it was just another wandering albatross. The differences between these two types of albatross are almost impossible for the amateur to discern. Similarly, the prions are so similar (to my untrained eye) that the only way to distinguish one from another would be to line up a specimen of each type of prion, and measure their bills.

There wasn’t enough time for us to become expert seabird spotters before we went away, but this book enabled me to make several identifications, including of juvenile and adult birds of the same species. This was pleasing. When it comes to the prions, I am satisfied to know the genus; the species is for those with more time and knowledge than I. I anticipate that it will be of future use in naming and learning about the birds we see in False Bay, and if we ever do a pelagic birding trip – which is on the to do list – it’ll be of great use there, too.

There’s an excellent review, from a real birder, over here.

You can get a copy of the book here. If you’re outside South Africa, get it here or here.

Article: Outside on shark repellents

A recurring but seemingly never-resolved question that intrigues shark researchers and management entities is that of whether there exists a reliable, non-lethal shark repellent.

Such a shark repellent would solve all manner of management problems: organisations like Shark Spotters exist partly to navigate that tense, thin line between sharks killing people and people killing sharks.

Furthermore, there would be a significant financial payoff associated with a successful patent of such a product. (I do not mean to suggest that this is the primary motivation for doing this kind of research, but untested, untestable products like this cannot possibly be marketed with anything else in mind.)

There are several ideas that have been either proposed, tested, or marketed. The SharkShield has been tested (not just by us), with mixed results. A shark repellent wetsuit has certainly been well publicised (there’s even a TED Talk), but, like medicines for pregnant women, I can’t see how it can be properly, ethically tested in order to state with some degree of certainty, in a statistical sense, that it works. The test described here has N=2, and there wasn’t a human in the suit.

I digress. Outside Online has an interesting article this month about the efforts by Eric Stroud, a pharmaceutical consultant, who – after much experimentation – settled on several compounds found in decaying shark flesh, which seem to work well as a repellent of about 30 species of mostly coastal sharks. The compound can also be synthesised, although the real thing, from a dead shark, apparently works better. Stroud’s financial backers travelled to Mossel Bay to visit Oceans Research, a multi-disciplinary research organisation with several shark scientists on its staff, to test the chemical on great white sharks. The article provides an overview of the history of shark repellent technology, and brings us up to date with this new chemical alternative. It’s early days…

Read the full article here. And remember, kids, that while the only thing that will keep you completely safe from a shark is not going into the sea at all, there are a bunch of simple, sensible things you can do to reduce your chances of meeting a man in a grey suit. Do them!

Article: The Atlantic on booming cephalopod populations

Let’s not quit our contemplation of the remarkable octopus just yet. For The Atlantic, the wonderful Ed Yong reports on a long-term (since the 1960s) trend of increasing cephalopod populations in the world’s oceans. Cephalopods are octopus, squid, and cuttlefish. The first paragraph of Yong’s article describes cuttlefish in Australian waters that are “the size and weight of a corgi”. I’m hooked (and slightly alarmed).

Scientists have found that, while there are short-term fluctuations, the overall trend in all kinds of cephalopod populations is up. The populations for which data was collected – largely from fisheries – live in all parts of the ocean, in both hemispheres, suggesting that a global phenomenon is affecting their breeding and survival success rates. Climate change and our overfishing of the ocean’s other inhabitants, as Yong points out, are obvious potential candidates here.

This issue is particularly relevant given the presence of an octopus fishery in False Bay, but unfortunately no one knows how successful that fishery has been (and I don’t buy anecdotal evidence on this – give me data).

Read the full article here.

Bookshelf: The Soul of an Octopus

The Soul of an Octopus: A Surprising Exploration Into the Wonder of Consciousness – Sy Montgomery

Naturalist and author Sy Montgomery delves deep into the life and times of octopus. The intelligence of these animals is relatively well known, but in The Soul of an Octopus Montgomery chronicles what might be called the “personalities” of several animals that she interacts with at Boston’s New England Aquarium, other aquaria, and reefs in the wild. The idea of an animal as apparently simple as an octopus having a personality may seem to be dangerously renegade. But, as we’ve seen, it may be an idea whose time has come. If you’re interested in this, Carl Safina’s Beyond Words is a good place to go after this book.

In addition to being a love letter to the octopus she meets, Montgomery’s book is a chronicle of the importance of aquariums and the people who work at aquariums: volunteers, in particular. This aspect of the book specially moved me, as I could identify with the ways in which the author and her friends at the aquarium were enriched and changed by their time as volunteers.

The Soul of an Octopus is thus more a speculative meditation and a memoir than a scientific treatise on cephalopods. I loved this book and recommend it to readers whose expectations regarding its content are calibrated appropriately. For a sample of Sy Montgomery’s writing about octopus, this article from Orion magazine is excellent. You could also read The Guardian‘s review.

You can get a copy of the book here (South Africa), here or here.

Just want to look at octopus? You could look at this one pretending to be a piece of kelp, this tiny baby one, this one in the warm, clear waters of southern Mozambique, and this one at night.

Newsletter: Warmer and warmer

Hi divers

Weekend dive plans

Friday: Shore diving at Long Beach at 10.00 am

Saturday: Launching from False Bay Yacht Club at 7.00 am for a double tank dive

The days are getting longer and the daytime temperatures are slowly creeping upwards… Well, on some days. Saturday looks like a better bet for False Bay with Hout Bay being an option on Sunday. The water colour off Dungeons has improved slightly today.

Tomorrow I am shore diving students at Long Beach at 10.00 am. On Saturday we will do an early False Bay double tank dive at 7.00 am. Let me know if you’d like to get wet.

Here’s a little bit of reading on the octopus fishery in False Bay (courtesy of Yvette!). This NSRI blog post, and the comments, are also required reading.

Coming up

As part of First Thursdays, you can attend the opening of the Birdlife Oceans of Life photographic exhibition at the South African Museum on the evening of Thursday 6 October. There’s information here (facebook) – this year’s exhibition includes a retrospective of the last few years’ best images.

Diversnight is on Saturday 7 November, so start charging your torches!

regards

Tony Lindeque
076 817 1099
www.learntodivetoday.co.za
www.learntodivetoday.co.za/blog/

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Monitoring the Oceans from Space MOOC

As your self-appointed education officer and fellow perpetual student, it is my duty to inform you of an upcoming MOOC on the Futurelearn platform, entitled “Monitoring the Oceans from Space“. In the five weeks of the course, which starts on 24 October, you will learn about using satellite data to monitor the health of the oceans. You will also learn how to access some of the ocean monitoring data that is collected every day about weather phenomena, icebergs, sea levels, ocean temperature, and more. If you’re into creating your own visualisations or crunching numbers yourself, this should appeal.

The course is presented by EUMETSAT and was developed by Imperative Space in partnership with Plymouth Marine Laboratory, the National Oceanography Centre (Southampton), CLS France and NASA JPL.

Read more about the MOOC here, and register here.

Here’s a trailer:

[youtube=”https://www.youtube.com/watch?v=p8hKomGzZ68&w=540″]

Regular service on this blog should resume in the forseeable future; it’s been a heck of a year, so forgive us!

Sharks! MOOC videos (part II)

Here is a selection of the videos for weeks three and four of the recent Sharks! MOOC hosted on edX. You can find weeks one and two here. All the videos are available on youtube if you’re really interested – you can check out the channel containing all this year’s videos, or a giant playlist containing all the videos from the 2015 iteration of the course.